<template>
  <div>
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>添加商品</el-breadcrumb-item>
    </el-breadcrumb>

    <el-card>
      <el-alert
        title="添加商品信息"
        type="info"
        show-icon
        :closable="false"
        >
      </el-alert>

      <!-- 步骤条 -->
      <!-- activeIndex - 0 字符串转为数值 -->
      <el-steps :space="200" :active="activeIndex - 0" finish-status="success" align-center>
        <el-step title="基本信息"></el-step>
        <el-step title="商品参数"></el-step>
        <el-step title="商品属性"></el-step>
        <el-step title="商品图片"></el-step>
        <el-step title="商品内容"></el-step>
        <el-step title="完成"></el-step>
      </el-steps>

      <el-form :model="addForm" :rules="addFormRules" ref="addFormRef" label-width="100px" label-position="top"><!-- label-position 表单域标签的位置 -->
        <!-- 标签页 -->
        <!-- before-leave 切换标签之前的钩子，若返回 false 或者返回 Promise 且被 reject，则阻止切换 -->
        <!-- tab-click tab 被选中时触发 -->
        <el-tabs tab-position="left" v-model="activeIndex" :before-leave="beforeTabLeave" @tab-click="tabClicked">
          <el-tab-pane label="基本信息" name="0">
            <el-form-item label="商品名称" prop="goods_name">
              <el-input v-model="addForm.goods_name"></el-input>
            </el-form-item>
            <el-form-item label="商品价格" prop="goods_price">
              <el-input v-model="addForm.goods_price" type="number"></el-input>
            </el-form-item>
            <el-form-item label="商品数量" prop="goods_number">
              <el-input v-model="addForm.goods_number" type="number"></el-input>
            </el-form-item>
            <el-form-item label="商品重量" prop="goods_weight">
              <el-input v-model="addForm.goods_weight" type="number"></el-input>
            </el-form-item>
            <el-form-item label="商品分类" prop="goods_cat">
              <!-- 商品分类级联选择器 -->
              <el-cascader
                :options="cateList"
                :props="cascaderProps"
                v-model="addForm.goods_cat"
                @change="cateChanged"
                >
              </el-cascader>
            </el-form-item>
          </el-tab-pane>
          
          <el-tab-pane label="商品参数" name="1">
            <el-form-item v-for="manyData in manyTabData" :key="manyData.attr_id" :label="manyData.attr_name">
              <!-- 复选框组 -->
              <el-checkbox-group v-model="manyData.attr_vals">
                <el-checkbox :label="val" v-for="(val, index) in manyData.attr_vals" :key="index" border></el-checkbox>
              </el-checkbox-group>

            </el-form-item>
          </el-tab-pane>

          <el-tab-pane label="商品属性" name="2">
            <el-form-item v-for="onlyData in onlyTabData" :key="onlyData.attr_id" :label="onlyData.attr_name">
              <el-input v-model="onlyData.attr_vals"></el-input>
            </el-form-item>
          </el-tab-pane>
          <el-tab-pane label="商品图片" name="3">
            <!-- 图片上传组件 -->
            <!-- action 图片要上传到的后台API -->
            <!-- on-preview 预览事件 -->
            <!-- on-remove 移除事件 -->
            <!-- file-list 文件列表 -->
            <!-- list-type 文件列表类型 -->
            <!-- el-upload未使用axios请求，内部封装，token验证不通过，设置请求头携带token认证 -->
            <!-- on-success 文件上传成功时的钩子 -->
            <el-upload
              class="upload-demo"
              :action="uploadURL"
              :on-preview="handlePreview"
              :on-remove="handleRemove"
              list-type="picture"
              :headers="headerObj"
              :on-success="handleSuccess"
              >
              <el-button size="small" type="primary">点击上传</el-button>
              <div slot="tip" class="el-upload__tip">只能上传jpg/png文件，且不超过500kb</div>
            </el-upload>
          </el-tab-pane>
          <el-tab-pane label="商品内容" name="4">
            <quill-editor
              v-model="addForm.goods_introduce"
            >
            </quill-editor>
            <el-button type="primary" class="addBtn" @click="add">添加商品</el-button>
          </el-tab-pane>
        </el-tabs>

      </el-form>

    </el-card>

    <!-- 图片预览对话框 -->
    <el-dialog
      title="图片预览"
      :visible.sync="previewVisible"
      width="40%"
      >
      <img :src="previewPath" style="width: 100%;">
    </el-dialog>

  </div>
</template>
<script>
import _ from 'lodash';
export default {
  data() {
    return {
      activeIndex: '0', // 步骤条默认
      addForm: {  // 添加商品表单对象
        goods_name: '',
        goods_price: 0,
        goods_number: 0,
        goods_weight: 0,
        goods_cat: 0,
        pics: [], // 上传的图片临时路径（对象）
        goods_introduce: '', // 商品介绍
        attrs: []
      },
      addFormRules: {
        goods_name: [
          { required: true, message: '请输入商品名称', trigger: 'blur' },
          { min: 1, max: 10, message: '长度在 1 到 10 个字符', trigger: 'blur' }
        ],
        goods_price: [
          { required: true, message: '请输入商品价格', trigger: 'blur' },
        ],
        goods_number: [
          { required: true, message: '请输入商品数量', trigger: 'blur' },
        ],
        goods_weight: [
          { required: true, message: '请输入商品重量', trigger: 'blur' },
        ],
        goods_cat: [
          { required: true, message: '请选择商品分类', trigger: 'blur' },
        ],
      },
      cateList: [],
      cascaderProps: {
        value: 'cat_id',
        label: 'cat_name',
        children: 'children',
        expandTrigger: 'hover'
      },
      manyTabData: [],  // 动态参数列表数据
      onlyTabData: [],  // 静态属性列表数据
      uploadURL: 'http://127.0.0.1:8888/api/private/v1/upload', // 上传图片的URL地址
      headerObj: { // el-upload组件请求头配置
        Authorization: window.sessionStorage.getItem('token')
      },
      previewPath: '', // 预览图片路径
      previewVisible: false, // 控制图片预览对话框显示隐藏
    }
  },
  created() {
    this.getCateList();
  },
  methods: {
    async getCateList() {
      const {data: res} = await this.$http.get('categories');
      if(res.meta.status != 200) return this.$message.error('获取商品分类失败');
      this.cateList = res.data;
    },
    cateChanged() {
      // console.log(this.addForm.goods_cat);
      if(this.addForm.goods_cat.length !== 3) { // 限制只能选择第三级分类
        this.addForm.goods_cat = [];
      }
    },
    beforeTabLeave(activeName, oldActiveName) {  // 为满足条件，阻止标签页切换
      /* console.log('即将离开标签页：' + oldActiveName + '；进入标签页：' +activeName);
      return false; */
      if(oldActiveName === '0' && this.addForm.goods_cat.length !== 3) {
        this.$message.error('请选择商品分类');
        return false;
      }
    },
    async tabClicked() {
      // console.log(this.addForm.goods_cat[this.addForm.goods_cat.length - 1]);
      if(this.activeIndex === '1') {  // 访问了动态参数面板
        const {data: res} = await this.$http.get(`categories/${this.cateId}/attributes`, {params: {sel: 'many'}});
        if(res.meta.status != 200) return this.$message.error('获取动态参数失败');
        res.data.forEach(item => {
          item.attr_vals = item.attr_vals.length !== 0 ? item.attr_vals.split(' ') : [];
        })
        this.manyTabData = res.data;
        // console.log(this.manyTabData);
      } else if(this.activeIndex === '2') { // 访问了静态属性面板
        const {data: res} = await this.$http.get(`categories/${this.cateId}/attributes`, {params: {sel: 'only'}});
        if(res.meta.status != 200) return this.$message.error('获取动态参数失败');
        this.onlyTabData = res.data;
        // console.log(this.onlyTabData);
      }
    },
    handlePreview(file) { // 图片上传组件预览事件
      // console.log(file);
      this.previewPath = file.response.data.url;
      this.previewVisible = true;
    },
    handleRemove(file) {  // 图片上传组件移除事件
      // console.log(file);
      // 1. 获取将要删除的临时路径
      const filePath =  file.response.data.tmp_path;
      // 2. 从pics数组中，找到这个图片对应的索引值
      const i = this.addForm.pics.findIndex(x => x.pic === filePath);
      // 3. 调用数组的splice 方法，把图片信息对象，从pics数组中移除
      this.addForm.pics.splice(i, 1);
      // console.log(this.addForm);
    },
    handleSuccess(response) { // 图片上传成功事件
      if(response.meta.status != 200) return this.$message.error('图片上传失败');
       // 1. 拼接图片信息对象
      const picPath = {pic: response.data.tmp_path};
       // 2. 图片信息对象push到pics数组中
      this.addForm.pics.push(picPath);
      // console.log(this.addForm);
    },
    add() {
      // console.log(this.addForm);
      this.$refs.addFormRef.validate(async valid => {
        if(!valid) return this.$message.error('请填写必须表单项');
        // 执行添加业务逻辑
        // this.addForm.goods_cat = this.addForm.goods_cat.join(',');  // 级联选择器绑定goods_cat为数组，这里转为字符串会报错，使用lodash对this.addForm深拷贝
        const form = _.cloneDeep(this.addForm);
        form.goods_cat = form.goods_cat.join(',');
        // 处理动态参数
        this.manyTabData.forEach(item => {
            const newInfo = {
            attr_id: item.attr_id,
            attr_value: item.attr_vals.join(' ')
          }
          this.addForm.attrs.push(newInfo);
        })
        console.log(this.addForm);
        // 处理静态属性
        this.onlyTabData.forEach(item => {
          const newInfo = {
            attr_id: item.attr_id,
            attr_value: item.attr_vals
          }
          this.addForm.attrs.push(newInfo);
        })
        form.attrs = this.addForm.attrs;
        console.log(form);
        // 提交商品
        const {data: res} = await this.$http.post('goods', form);
        console.log(res);
        if(res.meta.status !== 201) return this.$message.error('添加商品错误');
        this.$message.success('添加商品成功');
        this.$router.push('/goods');  // 跳转到商品页
      })
    }
  },
  computed: {
    cateId() {
      if(this.addForm.goods_cat.length === 3) {
        return this.addForm.goods_cat[2];
      } else {
        return null;
      }
    }
  }
}
</script>
<style lang="less" scoped>
  .el-checkbox{margin: 0 10px 0 0!important;}
  .addBtn{margin-top: 15px;}
</style>